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</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="iterator.concepts.traversal"></a><a class="link" href="traversal.html" title="Traversal">Traversal</a>
</h3></div></div></div>
<div class="toc"><dl class="toc">
<dt><span class="section"><a href="traversal.html#iterator.concepts.traversal.incrementable">Incrementable
        Iterator Concept</a></span></dt>
<dt><span class="section"><a href="traversal.html#iterator.concepts.traversal.single_pass">Single Pass
        Iterator Concept</a></span></dt>
<dt><span class="section"><a href="traversal.html#iterator.concepts.traversal.forward">Forward Traversal
        Concept</a></span></dt>
<dt><span class="section"><a href="traversal.html#iterator.concepts.traversal.bidirectional">Bidirectional
        Traversal Concept</a></span></dt>
<dt><span class="section"><a href="traversal.html#iterator.concepts.traversal.random_access">Random Access
        Traversal Concept</a></span></dt>
</dl></div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="iterator.concepts.traversal.incrementable"></a><a class="link" href="traversal.html#iterator.concepts.traversal.incrementable" title="Incrementable Iterator Concept">Incrementable
        Iterator Concept</a>
</h4></div></div></div>
<p>
          A class or built-in type <code class="computeroutput"><span class="identifier">X</span></code>
          models the <span class="bold"><strong>Incrementable Iterator</strong></span> concept
          if, in addition to <code class="computeroutput"><span class="identifier">X</span></code> being
          Assignable and Copy Constructible, the following expressions are valid
          and respect the stated semantics.
        </p>
<div class="table">
<a name="iterator.concepts.traversal.incrementable.incrementable_iterator_requireme"></a><p class="title"><b>Table 1.5. Incrementable Iterator Requirements (in addition to Assignable,
          Copy Constructible)</b></p>
<div class="table-contents"><table class="table" summary="Incrementable Iterator Requirements (in addition to Assignable,
          Copy Constructible)">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                  <p>
                    Expression
                  </p>
                </th>
<th>
                  <p>
                    Return Type
                  </p>
                </th>
<th>
                  <p>
                    Assertion/Semantics
                  </p>
                </th>
</tr></thead>
<tbody>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">++</span><span class="identifier">r</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">&amp;</span><span class="identifier">r</span>
                    <span class="special">==</span> <span class="special">&amp;++</span><span class="identifier">r</span></code>
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">r</span><span class="special">++</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span></code>
                  </p>
                </td>
<td>
<pre class="programlisting"><span class="special">{</span>
  <span class="identifier">X</span> <span class="identifier">tmp</span> <span class="special">=</span> <span class="identifier">r</span><span class="special">;</span>
  <span class="special">++</span><span class="identifier">r</span><span class="special">;</span>
  <span class="keyword">return</span> <span class="identifier">tmp</span><span class="special">;</span>
<span class="special">}</span>
</pre>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">iterator_traversal</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                  </p>
                </td>
<td>
                  <p>
                    Convertible to <code class="computeroutput"><span class="identifier">incrementable_traversal_tag</span></code>
                  </p>
                </td>
<td>
                </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break">
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="iterator.concepts.traversal.single_pass"></a><a class="link" href="traversal.html#iterator.concepts.traversal.single_pass" title="Single Pass Iterator Concept">Single Pass
        Iterator Concept</a>
</h4></div></div></div>
<p>
          A class or built-in type <code class="computeroutput"><span class="identifier">X</span></code>
          models the <span class="bold"><strong>Single Pass Iterator</strong></span> concept
          if the following expressions are valid and respect the stated semantics.
        </p>
<div class="table">
<a name="iterator.concepts.traversal.single_pass.single_pass_iterator_requirement"></a><p class="title"><b>Table 1.6. Single Pass Iterator Requirements (in addition to Incrementable
          Iterator and Equality Comparable)</b></p>
<div class="table-contents"><table class="table" summary="Single Pass Iterator Requirements (in addition to Incrementable
          Iterator and Equality Comparable)">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                  <p>
                    Expression
                  </p>
                </th>
<th>
                  <p>
                    Return Type
                  </p>
                </th>
<th>
                  <p>
                    Assertion/Semantics / Pre-/Post-condition
                  </p>
                </th>
</tr></thead>
<tbody>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">++</span><span class="identifier">r</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>
                  </p>
                </td>
<td>
                  <p>
                    pre:<br> <code class="computeroutput"><span class="identifier">r</span></code>
                    is dereferenceable;<br> post:<br> <code class="computeroutput"><span class="identifier">r</span></code>
                    is dereferenceable or<br> <code class="computeroutput"><span class="identifier">r</span></code>
                    is past-the-end
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">==</span>
                    <span class="identifier">b</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to <code class="computeroutput"><span class="keyword">bool</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">==</span></code> is an equivalence
                    relation over its domain
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">!=</span>
                    <span class="identifier">b</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to <code class="computeroutput"><span class="keyword">bool</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">!(</span><span class="identifier">a</span>
                    <span class="special">==</span> <span class="identifier">b</span><span class="special">)</span></code>
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">iterator_traits</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">&gt;::</span><span class="identifier">difference_type</span></code>
                  </p>
                </td>
<td>
                  <p>
                    A signed integral type representing the distance between iterators
                  </p>
                </td>
<td>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">iterator_traversal</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                  </p>
                </td>
<td>
                  <p>
                    Convertible to<code class="computeroutput"><span class="identifier">single_pass_traversal_tag</span></code>
                  </p>
                </td>
<td>
                </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break">
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="iterator.concepts.traversal.forward"></a><a class="link" href="traversal.html#iterator.concepts.traversal.forward" title="Forward Traversal Concept">Forward Traversal
        Concept</a>
</h4></div></div></div>
<p>
          A class or built-in type <code class="computeroutput"><span class="identifier">X</span></code>
          models the <span class="bold"><strong>Forward Traversal</strong></span> concept if,
          in addition to <code class="computeroutput"><span class="identifier">X</span></code> meeting
          the requirements of Default Constructible and Single Pass Iterator, the
          following expressions are valid and respect the stated semantics.
        </p>
<div class="table">
<a name="iterator.concepts.traversal.forward.forward_traversal_iterator_requi"></a><p class="title"><b>Table 1.7. Forward Traversal Iterator Requirements (in addition to Default
          Constructible and Single Pass Iterator)</b></p>
<div class="table-contents"><table class="table" summary="Forward Traversal Iterator Requirements (in addition to Default
          Constructible and Single Pass Iterator)">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                  <p>
                    Expression
                  </p>
                </th>
<th>
                  <p>
                    Return Type
                  </p>
                </th>
<th>
                  <p>
                    Assertion/Note
                  </p>
                </th>
</tr></thead>
<tbody>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span> <span class="identifier">u</span><span class="special">;</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>
                  </p>
                </td>
<td>
                  <p>
                    note: <code class="computeroutput"><span class="identifier">u</span></code> may have
                    a singular value.
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">++</span><span class="identifier">r</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">r</span> <span class="special">==</span>
                    <span class="identifier">s</span></code> and <code class="computeroutput"><span class="identifier">r</span></code> is dereferenceable implies
                    <code class="computeroutput"><span class="special">++</span><span class="identifier">r</span>
                    <span class="special">==</span> <span class="special">++</span><span class="identifier">s</span><span class="special">.</span></code>
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">iterator_traversal</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                  </p>
                </td>
<td>
                  <p>
                    Convertible to <code class="computeroutput"><span class="identifier">forward_traversal_tag</span></code>
                  </p>
                </td>
<td>
                </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break">
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="iterator.concepts.traversal.bidirectional"></a><a class="link" href="traversal.html#iterator.concepts.traversal.bidirectional" title="Bidirectional Traversal Concept">Bidirectional
        Traversal Concept</a>
</h4></div></div></div>
<p>
          A class or built-in type <code class="computeroutput"><span class="identifier">X</span></code>
          models the <span class="bold"><strong>Bidirectional Traversal</strong></span> concept
          if, in addition to <code class="computeroutput"><span class="identifier">X</span></code> meeting
          the requirements of Forward Traversal Iterator, the following expressions
          are valid and respect the stated semantics.
        </p>
<div class="table">
<a name="iterator.concepts.traversal.bidirectional.bidirectional_traversal_iterator"></a><p class="title"><b>Table 1.8. Bidirectional Traversal Iterator Requirements (in addition to Forward
          Traversal Iterator)</b></p>
<div class="table-contents"><table class="table" summary="Bidirectional Traversal Iterator Requirements (in addition to Forward
          Traversal Iterator)">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                  <p>
                    Expression
                  </p>
                </th>
<th>
                  <p>
                    Return Type
                  </p>
                </th>
<th>
                  <p>
                    Assertion/Semantics/Pre-/Post-condition
                  </p>
                </th>
</tr></thead>
<tbody>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">--</span><span class="identifier">r</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>
                  </p>
                </td>
<td>
                  <p>
                    pre: there exists <code class="computeroutput"><span class="identifier">s</span></code>
                    such that <code class="computeroutput"><span class="identifier">r</span> <span class="special">==</span> <span class="special">++</span><span class="identifier">s</span></code>.<br> post: <code class="computeroutput"><span class="identifier">s</span></code> is dereferenceable. <code class="computeroutput"><span class="special">--(++</span><span class="identifier">r</span><span class="special">)</span> <span class="special">==</span>
                    <span class="identifier">r</span></code>. <code class="computeroutput"><span class="special">--</span><span class="identifier">r</span> <span class="special">==</span>
                    <span class="special">--</span><span class="identifier">s</span></code>
                    implies <code class="computeroutput"><span class="identifier">r</span> <span class="special">==</span>
                    <span class="identifier">s</span></code>. <code class="computeroutput"><span class="special">&amp;</span><span class="identifier">r</span> <span class="special">==</span>
                    <span class="special">&amp;--</span><span class="identifier">r</span></code>.
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">r</span><span class="special">--</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to <code class="computeroutput"><span class="keyword">const</span> <span class="identifier">X</span><span class="special">&amp;</span></code>
                  </p>
                </td>
<td>
<pre class="programlisting"><span class="special">{</span>
  <span class="identifier">X</span> <span class="identifier">tmp</span> <span class="special">=</span> <span class="identifier">r</span><span class="special">;</span>
  <span class="special">--</span><span class="identifier">r</span><span class="special">;</span>
  <span class="keyword">return</span> <span class="identifier">tmp</span><span class="special">;</span>
<span class="special">}</span>
</pre>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">iterator_traversal</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                  </p>
                </td>
<td>
                  <p>
                    Convertible to <code class="computeroutput"><span class="identifier">bidirectional_traversal_tag</span></code>
                  </p>
                </td>
<td>
                </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break">
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="iterator.concepts.traversal.random_access"></a><a class="link" href="traversal.html#iterator.concepts.traversal.random_access" title="Random Access Traversal Concept">Random Access
        Traversal Concept</a>
</h4></div></div></div>
<p>
          A class or built-in type <code class="computeroutput"><span class="identifier">X</span></code>
          models the <span class="bold"><strong>Random Access Traversal</strong></span> concept
          if the following expressions are valid and respect the stated semantics.
          In the table below, <code class="computeroutput"><span class="identifier">Distance</span></code>
          is <code class="computeroutput"><span class="identifier">iterator_traits</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">&gt;::</span><span class="identifier">difference_type</span></code> and <code class="computeroutput"><span class="identifier">n</span></code>
          represents a constant object of type <code class="computeroutput"><span class="identifier">Distance</span></code>.
        </p>
<div class="table">
<a name="iterator.concepts.traversal.random_access.random_access_traversal_iterator"></a><p class="title"><b>Table 1.9. Random Access Traversal Iterator Requirements (in addition to Bidirectional
          Traversal)</b></p>
<div class="table-contents"><table class="table" summary="Random Access Traversal Iterator Requirements (in addition to Bidirectional
          Traversal)">
<colgroup>
<col>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                  <p>
                    Expression
                  </p>
                </th>
<th>
                  <p>
                    Return Type
                  </p>
                </th>
<th>
                  <p>
                    Operational Semantics
                  </p>
                </th>
<th>
                  <p>
                    Assertion/Precondition
                  </p>
                </th>
</tr></thead>
<tbody>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">r</span> <span class="special">+=</span>
                    <span class="identifier">n</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>
                  </p>
                </td>
<td>
<pre class="programlisting"><span class="special">{</span>
  <span class="identifier">Distance</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">n</span><span class="special">;</span>
  <span class="keyword">if</span> <span class="special">(</span><span class="identifier">m</span> <span class="special">&gt;=</span> <span class="number">0</span><span class="special">)</span>
    <span class="keyword">while</span> <span class="special">(</span><span class="identifier">m</span><span class="special">--)</span>
      <span class="special">++</span><span class="identifier">r</span><span class="special">;</span>
  <span class="keyword">else</span>
    <span class="keyword">while</span> <span class="special">(</span><span class="identifier">m</span><span class="special">++)</span>
      <span class="special">--</span><span class="identifier">r</span><span class="special">;</span>
  <span class="keyword">return</span> <span class="identifier">r</span><span class="special">;</span>
<span class="special">}</span>
</pre>
                </td>
<td>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">+</span>
                    <span class="identifier">n</span></code>, <code class="computeroutput"><span class="identifier">n</span>
                    <span class="special">+</span> <span class="identifier">a</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span></code>
                  </p>
                </td>
<td>
<pre class="programlisting"><span class="special">{</span>
  <span class="identifier">X</span> <span class="identifier">tmp</span> <span class="special">=</span> <span class="identifier">a</span><span class="special">;</span>
  <span class="keyword">return</span> <span class="identifier">tmp</span><span class="special">+=</span> <span class="identifier">n</span><span class="special">;</span>
<span class="special">}</span>
</pre>
                </td>
<td>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">r</span> <span class="special">-=</span>
                    <span class="identifier">n</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span><span class="special">&amp;</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="keyword">return</span> <span class="identifier">r</span>
                    <span class="special">+=</span> <span class="special">-</span><span class="identifier">n</span></code>
                  </p>
                </td>
<td>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">-</span>
                    <span class="identifier">n</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">X</span></code>
                  </p>
                </td>
<td>
<pre class="programlisting"><span class="special">{</span>
  <span class="identifier">X</span> <span class="identifier">tmp</span> <span class="special">=</span> <span class="identifier">a</span><span class="special">;</span>
  <span class="keyword">return</span> <span class="identifier">tmp</span><span class="special">-=</span> <span class="identifier">n</span><span class="special">;</span>
<span class="special">}</span>
</pre>
                </td>
<td>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">b</span> <span class="special">-</span>
                    <span class="identifier">a</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">Distance</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">&lt;</span>
                    <span class="identifier">b</span> <span class="special">?</span>
                    <span class="identifier">distance</span><span class="special">(</span><span class="identifier">a</span><span class="special">,</span><span class="identifier">b</span><span class="special">)</span>
                    <span class="special">:</span> <span class="special">-</span><span class="identifier">distance</span><span class="special">(</span><span class="identifier">b</span><span class="special">,</span><span class="identifier">a</span><span class="special">)</span></code>
                  </p>
                </td>
<td>
                  <p>
                    pre: there exists a value <code class="computeroutput"><span class="identifier">n</span></code>
                    of <code class="computeroutput"><span class="identifier">Distance</span></code> such
                    that <code class="computeroutput"><span class="identifier">a</span> <span class="special">+</span>
                    <span class="identifier">n</span> <span class="special">==</span>
                    <span class="identifier">b</span></code>. <code class="computeroutput"><span class="identifier">b</span>
                    <span class="special">==</span> <span class="identifier">a</span>
                    <span class="special">+</span> <span class="special">(</span><span class="identifier">b</span> <span class="special">-</span>
                    <span class="identifier">a</span><span class="special">)</span></code>.
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span><span class="special">[</span><span class="identifier">n</span><span class="special">]</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to T
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">*(</span><span class="identifier">a</span>
                    <span class="special">+</span> <span class="identifier">n</span><span class="special">)</span></code>
                  </p>
                </td>
<td>
                  <p>
                    pre: a is a <span class="bold"><strong>Readable Iterator</strong></span>
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span><span class="special">[</span><span class="identifier">n</span><span class="special">]</span>
                    <span class="special">=</span> <span class="identifier">v</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to T
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">*(</span><span class="identifier">a</span>
                    <span class="special">+</span> <span class="identifier">n</span><span class="special">)</span> <span class="special">=</span>
                    <span class="identifier">v</span></code>
                  </p>
                </td>
<td>
                  <p>
                    pre: a is a <span class="bold"><strong>Writable iterator</strong></span>
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">&lt;</span>
                    <span class="identifier">b</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to <code class="computeroutput"><span class="keyword">bool</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">b</span> <span class="special">-</span>
                    <span class="identifier">a</span> <span class="special">&gt;</span>
                    <span class="number">0</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">&lt;</span></code> is a total
                    ordering relation
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">&gt;</span>
                    <span class="identifier">b</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to <code class="computeroutput"><span class="keyword">bool</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">b</span> <span class="special">&lt;</span>
                    <span class="identifier">a</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">&gt;</span></code> is a total
                    ordering relation
                  </p>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">&gt;=</span>
                    <span class="identifier">b</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to <code class="computeroutput"><span class="keyword">bool</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">!(</span><span class="identifier">a</span>
                    <span class="special">&lt;</span> <span class="identifier">b</span><span class="special">)</span></code>
                  </p>
                </td>
<td>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">&lt;=</span>
                    <span class="identifier">b</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to <code class="computeroutput"><span class="keyword">bool</span></code>
                  </p>
                </td>
<td>
                  <p>
                    <code class="computeroutput"><span class="special">!(</span><span class="identifier">a</span>
                    <span class="special">&gt;</span> <span class="identifier">b</span><span class="special">)</span></code>
                  </p>
                </td>
<td>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">iterator_traversal</span><span class="special">&lt;</span><span class="identifier">X</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                  </p>
                </td>
<td>
                  <p>
                    convertible to <code class="computeroutput"><span class="identifier">random_access_traversal_tag</span></code>
                  </p>
                </td>
<td>
                </td>
<td>
                </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break">
</div>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer">Copyright © 2003, 2005 David Abrahams Jeremy Siek Thomas
      Witt<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at &lt;ulink url="http://www.boost.org/LICENSE_1_0.txt"&gt;
        http://www.boost.org/LICENSE_1_0.txt &lt;/ulink&gt;)
      </p>
</div></td>
</tr></table>
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